I should add, however, that I'm pretty sure the Avanti 3's don't go all the way down to 25 hertz. What you're asking for, at least without a sub, in that price range, would seem to be a rather tall order. I've heard that the Mahlers do go deeper than the Avantis, however.
After I heard the excellence of the small Totem Tabus, I thought that the Totem Shaman, at the time a 10K floorstander, would sound phenomenal, but it didn't, at least not to me, although it wasn't "bad". I was definitely disappointed, however. The older, three box version of the Audio Physic Caldera did sound phenomenal, and was available at the time for "only" 10,000 dollars, which was about half off the retail. But even that speaker didn't go down to 25 hertz, at least not flat, I'm almost certain.
The Mahlers MAY be the best bet of the three based on your criteria, but it would seem that an in home audition would be mandatory. Those reportedly require a fairly large room to sound their best, and it's not clear whether your room dimensions would be optimal for them, based on your statement that there's no room for two subwoofers.
Please let us know what you decide.
